Background: Previous studies reported the use of microRNAs (miRNAs) as diagnostic and/or prognostic biomarkers for various cancers, including gastric cancer (GC). This study evaluated the diagnostic and prognostic significance of serum miR-296-5p and miR-28-3p in GC. Materials and Methods: Serum samples of 90 patients with GC and 90 healthy individuals, and 20 pairs of tissue specimens from patients with GC were collected. The expression of miR-296-5p and miR-28-3p in both the serum and tissue samples were detected using quantitative real-time polymerase chain reaction analysis. The diagnostic and prognostic values of miR-296-5p and miR-28-3p were evaluated by using receiver operating characteristic curve and Kaplan-Meier analyses, respectively. Results: Compared with the healthy controls, the expression of miR-296-5p in the serum and tissues of patients with GC was significantly upregulated, whereas that of miR-28-3p was significantly downregulated. High miR-296-5p and low miR-28-3p levels in the serum significantly correlated with larger tumor size (>5 cm), lymph node metastasis, and TNM stage III+IV. The area under the curve values of miR-296-5p and miR-28-3p were 0.919 and 0.911, respectively, with high sensitivity and specificity. Kaplan-Meier survival curves showed that patients with GC with high level of miR-296-5p or low level of miR-1236-3p in the serum had the poorest overall survival. COX analysis showed that lymphatic metastasis, high miR-296-5p expression, and low miR-28-3p expression are independent parameters indicating poor prognosis in GC. Conclusion: Our findings indicate that serum miR-296-5p and miR-28-3p levels are potential biomarkers in the diagnosis and prognosis of GC.
Keywords: diagnosis; gastric cancer; miR-28-3p; miR-296-5p; prognosis.